Pyloroplasty

Pyloroplasty (surgical alteration of the pylorus) is almost never performed alone. In virtually all cases, it is performed as an adjunct to another procedure (most commonly vagotomy). It can be performed on a diseased (narrowed or thickened) pylorus or on a normal pylorus.

Pyloroplasty completely destroys the pyloric sphincter and drains the stomach continuously into the duodenum. At the same time, however, it results in rapid emptying of the stomach into the duodenum (causing dumping) and allows reflux of the duodenal contents back into the stomach (causing bile gastritis).

There are several types of pyloroplasty, as follows:

• Heineke-Mikulicz pyloroplasty involves a longitudinal incision across the pylorus that is closed transversely; this is the most commonly performed pyloroplasty
• Jaboulay pyloroplasty involves a side-to-side gastroduodenostomy without a pylorus incision (ie, the pylorus remains intact)
• Finney pyloroplasty also involves a side-to-side gastroduodenostomy but with a pylorus incision (ie, the pylorus is divided)

Pyloromyotomy and pyloric dilatation are lesser variants of pyloroplasty. Gastrojejunostomy and antrectomy (~50% of the distal portion of the stomach) are alternatives to pyloroplasty as an adjunct to vagotomy.

Pyloroplasty is most commonly performed as a gastric drainage procedure that is adjunctive to vagotomy for peptic ulcer disease (PUD). (Truncal vagotomy [TV] and selective vagotomy [SV] denervate the pylorus and require pyloric drainage; highly selective vagotomy [HSV] spares the pylorus and does not require a drainage procedure.) With the availability of H2-receptor anatgonists (H2RAs) and proton pump inhibitors (PPIs), however, elective indications for surgery for PUD have decreased. ^[1]

In addition, pyloroplasty can be performed as the first step in the surgical control of a bleeding duodenal ulcer and, rarely, for perforated duodenal ulcer. This is pyloroplasty in a normal pylorus.

Pyloroplasty is also performed as an adjunct to inadvertent vagotomy in esophagectomy and proximal gastrectomy. This is pyloroplasty in a normal pylorus. However, pyloroplasty as an adjunct to inadvertent vagotomy in patients undergoing esophagectomy is being questioned, and some surgeons do not perform it or perform pyloromyotomy or pyloric dilatation only. ^{[2, 3]} Endoscopic balloon dilatation of the pylorus is an alternative to surgical pyloroplasty. ^[4] Intraoperative botulinum toxin (BT) injection has been used to treat delayed gastric emptying (DGE)  following esophagectomy. ^[5] Endoscopic pyloric intervention has also been used as therapy for DGE.

Less common indications include pyloric atresia in infants and refractory gastroparesis in elderly patients. A retrospective study by Mancini et al found pyloroplasty to be highly effective for management of refractory gastroparesis. ^[6]  Others have reported similar results. ^[7]  Gastric peroral endoscopic pyloromyotomy (G-POEM or POP) as an endoscopic modality for treatment of refractory gastroparesis has been reported. ^[8]  The success rate for this procedure is reported to be 100%, with a short-term (≤ 1 y) success rate in the range of 50-80%. The duration of this procedure ranges from 50 to 70 min, and the usual length of hospital stay is 2-3 days. 

In elective situations, vagotomy is performed first, followed by pyloroplasty. In an emergency (bleeding and perforation), the pylorus is handled first, and vagotomy follows.

Heineke-Mikulicz pyloroplasty should not be performed in the presence of chronic duodenal ulcer with extensive fibrosis, scarring, and induration (Jaboulay pyloroplasty may be performed).

Pyloroplasty is not performed alone; it should be performed in combination with vagotomy (truncal or selective).

Anatomy

The stomach wall consists of the following:

• Outer serosa (visceral peritoneum)
• A thick layer of (smooth) muscles arranged in three layers—namely, outer longitudinal, middle circular (which forms the pylorus), and inner oblique (which is unique to the stomach)
• Submucosa, which contains a rich network of blood vessels
• Innermost mucosa, which consists of lamina propria, muscularis mucosa, and columnar epithelium

The mucosa and submucosa are thrown into several longitudinal folds called rugae.

Best practices

Pyloroplasty is generally superior to gastrojejunostomy (the other drainage procedure), in that it is more physiologic (ie, it maintains the normal gastroduodenal continuity). In contrast, gastrojejunostomy bypasses the duodenum and causes more dumping and bile reflux.

Pyloroplasty should not be performed in the presence of fibrosed and scarred pyloroduodenum in chronic duodenal ulcer.

In making the incision, it must be remembered that the wall is thick in the antropylorus but thin in the duodenum.

Pyloromyotomy and pyloric dilatation are lesser gastric drainage options than pyloroplasty. During pyloromyotomy, electrocauterization is avoided in deeper parts of the muscle to avoid an inadvertent opening of the mucosa.

Complication prevention

The incision across the pylorus should be of adequate length on both sides (ie, stomach and duodenum). A single-layer approach decreases the amount of inversion, as well as the risk of narrowing and gastric outlet obstruction (GOO).

In the performance of pyloromyotomy, care should be exercised to avoid opening of the duodenal (and, less commonly, gastric) mucosa.